Spas with thermal pool

Băile Herculane, Caraș-Severin

Hotel-based thermal spa in Băile Herculane with sulfur mineral baths, indoor and outdoor pools, jacuzzi and sauna, open to hotel guests.

Ubud, Bali

An adults-only wellness retreat on Ubud's Ayung River offering multi-day healing programmes, thermal circuits and plant-based cuisine by reservation only.

Băile Herculane, Caraș-Severin

A 4-star hotel in central Băile Herculane with thermal pools, saunas, balneo and physiotherapy treatments, open to overnight guests.

Puyehue, Los Lagos

A forest resort spa in Puyehue, Chile, with volcanic thermal pools and outdoor baths, open only to hotel guests.

Jūrmala

A hotel spa on Jūrmala's Jomas iela with saunas and thermal pools, open only to guests of the hotel.

Tucson, Arizona

Lakeside Spa at this 398-room desert resort in Tucson is open to hotel guests only, with two heated pools, a Jacuzzi and mountain views of Catalina range.

Hot Springs, Arkansas

A café and lounge inside Thai-Me Spa in downtown Hot Springs, with outdoor mineral soaking spas, cold plunge and sauna access nearby.

Bursa

Hotel spa in Bursa's Çekirge thermal district, guests-only access, with a thermal pool, hamam rituals and massage packages tied to multi-night stays.

Milan, Lombardy

Adults-only day spa in a Liberty-style building near Milan's Parco Sempione, with thermal pools, saunas, steam room and a hydrotherapy circuit.

Bad Ischl, Upper Austria

A salt-and-brine thermal bath complex in Bad Ischl with indoor/outdoor pools, a sauna world, and a rooftop wellness deck at the attached hotel.

Punta Cana, La Altagracia

Upscale day spa in Punta Cana offering massages, facials, a thermal pool and ocean-view relaxation lounges, open daily 9am-7pm.

Charlotte, North Carolina

A moderate-priced day spa in Charlotte's SouthPark area with a sauna, steam room and thermal pool alongside massage, facial and body-treatment menus.

Băile Felix, Bihor

Strand Apollo-Felix is a year-round thermal pool complex in Băile Felix, Romania, with indoor and outdoor pools open daily from 8am to 8pm.

Tekapo, Canterbury

Outdoor hot pools, a cooler soak and a kids' aqua play area beside Lake Tekapo, with walk-in day passes and an on-site café.

Hot Springs, Arkansas

A day spa on Central Avenue in Hot Springs with outdoor mineral soaking tubs, cold plunge, infrared sauna, massage and an on-site café.

Santa Fe, New Mexico

Hotel spa at La Fonda on the Plaza in downtown Santa Fe, with a heated outdoor pool, hot tub, fitness center and relaxation lounge for guests of the hotel.

Leukerbad, Valais

Thermal baths inside a 19th-century hotel in Leukerbad, Valais, with mineral-rich pools open daily from 9am to 8pm.

Vals, Grisons

Peter Zumthor's quartzite thermal baths in Vals, fed by a 30°C mineral spring, open to day visitors as well as hotel guests.

Palm Beach, Florida

An oceanfront resort spa in Riviera Beach combining Ayurvedic treatments with a hydrothermal circuit, hammam, salon and private beach access.

Asan, South Chungcheong

Hot springs resort spa in Asan with thermal pools, sauna and a relaxation lounge, open daily on a walk-in day-pass basis.

Redstone Historic District, Colorado

A ranch property in Colorado's Crystal River Valley with three tiered natural hot springs pools open to day visitors and overnight guests alike.

Băile Felix, Bihor

A thermal baths complex in Băile Felix with outdoor and indoor pools, open daily with walk-in access and no membership required.

Portland, Oregon

Adults-only hotel and thermal springs on NE Alberta St in Portland, with vitality pools, a day-pass option, and spa treatments.

Carson, Washington

A clothing-optional, adults-only mineral hot springs bathhouse in Carson, Washington, with a $12 day pass and a $30 bath-and-wrap treatment.